Method of producing rayon



Patented June 2, 1936 UNITED STATES PATENT OFFICE METHOD OF PRODUCING RAYON Emil Kline, Buffalo, N. Y., assignor to Du Pont Rayon Company, New York, N. Y., a corporation oi Delaware No Drawing. Application July 22, 1930, Serial No. 469,911

21 Claims.

Wapd oligenweolluloslg deriva ives. More particularlyf it relates to a method of producing materials of the type mentioned having a low luster. Specifically, it relates to a method of producing rayon having a low luster and preferably equal to or lower than that possessed by natural silk.

Recently, there has been devised a method of producing rayon having a, subdued or diminished luster which comprises incorporating a compound, such as turpentine or kerosene, into a viscose solution at some stage in the preparation thereof, spinning the resultant solution and finishing the thread in the usual manner. During the finishing operation the added substance is substantially eliminated, and the product free of foreign or added materials possesses the desired luster characteristics. This product, when examined under the microscope at a magnification not exceeding 440 diameters, appears as a substantially solid thread showing no liquid, gas or solid particles. Its cross-section is similar to that of a lustrous thread except that the surface contour is crinkled, porous or channeled.

I have found that I can produce a product of the type previously described by incorporating in a spinning solution such as viscose prior to the spinning thereof certain organic substances containing one or more hydroxyl groups, such as the high molecular weight alcohols, including the higher aliphatic alcohols, aromatic alcohols, for example, those of the terpene group, phenols, etc. or certain organic compounds hereinafter more fully explained, and spinning and finishing the resultant thread in the usual manner, whereby the added material is substantially eliminated without the use of any special steps or operations.

It is therefore an object of this invention to provide a method for producing rayon having a low luster and preferably equal to or lower than possessed by natural silk.

Another object of this invention is to provide a method of producing rayon having a subdued luster which comprises incorporating a difficultly volatile organic compound such as an alcohol containing more than four carbon atoms in a spinning solution at some stage in the preparation thereof, spinning said solution, and finishing the thread in the usual manner, whereby the added material is substantially eliminated without employing special steps.

A specific object of this invention is to provide a method of producing artificial yarn of a subdued luster which comprises incorporating terpineol in a spinning solution at some stage in the preparation thereof, spinning said solution, and

finishing the thread in the usual manner, whereby the terpineol is automatically substantially eliminated.

Other objects will become apparent from the following description and appended claims.

In accordance with the principles of this invention, artificial thread having a mat appearance and a luster similar to or lower than natural silk is produced by spinning in the usual manner a cellulosic solution containing one or more substances, which substances are distilled or otherwise removed at one or more stages in the process of producing the finished thread without employing any special steps. When a viscose solution is used. The substance which may be added thereto should be insoluble in viscose, or, if soluble in viscose, insoluble in the coagulating bath liquor, said substance possessing a sufficiently low vapor pressure so that it will not be removed from the viscose prior to the spinning, particularly when said viscose is evacuated to remove the air, nor is it removed during spinning except in some instances a relatively small per cent may be removed, depending upon the substance chosen, said vapor pressure being sufiiciently high so that the substance may be automatically removed from the thread (as by steam distillation or otherwise) in the usual finishing operations, such as washing, desulphuring, bleaching, drying or other steps commonly used in the production of the material.

The substances which are capable of being used may be in any physical state. Solids, including stearyl alcohol, fenchyl alcohol, alpha terpineol and the like members of the terpene group, phenol, resorcinol, and B-naphthol produce satisfactory results. Good results are also secured by using liquids, such as the liquid terpineols, pine oil, amylene dichloride, tetrachlorethane and tetrachlorethylene. The higher liquid alcohols of the aliphatic series, and particularly those containing five or more carbon atoms, such as hexyl, n-heptyl and lauryl alcohols, also produce good results.

In practicing this process with viscose, one or a plurality of the above-mentioned compounds is introduced into the viscose prior to the spinning thereof and is automatically eliminated in the process of producing the finished thread. The substance may be incorporated in the viscose at any time between dissolving the cellulose xanthate 55 in caustic soda and the time the viscose is ready to be spun. It may also be added to the steeping caustic, to the alkali cellulose, or to the carbon disulphide. Preferably, it is added to the mixture of caustic soda, water and cellulose xanthate as those are being mixed. The substance may be added directly to the caustic solution or may be first mixed with a small amount of caustic and then added to the main charge. Preferably, an emulsion of the substance in water is separately prepared and this emulsion added to the batch. If desired, to aid in the emulsification any of the well-known emulsifying agents for this purpose, including soaps, gums, sulphonated vegetable oils, akylated naphthalene and anthraquinone sulphonic acids (such as the Nekals), may be employed.

The amount of the substance added depends on the desired luster. Satisfactory results have been obtained by incorporating approximately from 0.05% to 3.0% of the compound in a viscose solution of the usual type, the proportions being based on weight. The following specific examples indicate the preferred quantities of the various materials added:

Per cent Amylene dichloride, emulsified with Monopole oil Tetrachlorethane, emulsified with Monopole oil 0.5 Tetrachlorethylene, emulsified with Monopole oil 0.4 Fenchyl alcohol, emulsified with Monopole oil 0.4

' Terpineol, emulsified with Nekal A. E. M 0.4

Pine oil, emulsified with triethanolamine oleate 0.6

The process may be carried out as previously explained, but in order to more clearly illustrate one precise mode of operation, the following de-- scription of one procedure is given:

To a spinning charge of pounds of viscose produced in the usual manner there is added a thick, creamy emulsion containing 20 grams of a suitable emulsifying agent, such as triethanolamine oleate, 181.6 grams of a member of the terpene group, such as a-terpineol, and 200 cc. of water. The emulsion is preferably made by dis- 7 solving the triethanolamine oleate in the terpineol and then adding the water with constant agitation. Upon the introduction of the emulsion in the viscose, the mass is agitated until the distribution of the emulsion is complete. The viscose thus produced is allowed to ripen and is spun,

' and the thread produced processed in the usual manner.

Any of the well-known coagulating baths may be used. I prefer, however, to use one containing zinc or analogous metals. A bath which has given satisfactory results consists of 11% sulphuric acid, 24% sodium sulphate, and 0.8% zinc sulphate.

Although the invention has been described specifically in connection with artificial thread produced from viscose, it is not limited thereto. The principles of this invention are equally applicable to other cellulose spinning solutions, as, for instance, those containing cellulose derivatives such as cellulose acetate, cellulose ethers or the like. Furthermore, the invention is not restricted to the production of artificial thread. It is likewise suitable in the manufacture of sheets or films from cellulosio solutions of the type pre-- viously mentioned and including viscose, cellulose acetate and cellulose ethers.

The term extruding used in the claims is intended to cover generically the extrusion of the cellulosic solution from the spinnerets in the production of threads or the casting of the solutions to produce sheets or films.

Since it is obvious that various changes may be made in the specific details of operation above set forth without departing from the nature or spirit of this invention, this invention is not restricted thereto except as set forth in the appended claims.

I claim:

1. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding into an aqueous bath a cellulosic solution containing an organic substance of more than 4 carbon atoms and containing one or more hydroxyl groups, said substance possessing a vapor pressure such that it will not be re moved from the solution prior to extrusion and will be automatically removed in the spinning and in the subsequent operations employed in the production of the product, and finishing the extruded material in the usual manner employed in the production thereof whereby said organic substance is automatically substantially eliminated.

2. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding into an aqueous bath a eellulosic solution containing a substance comprising an alcohol of the terpene group, and finishing the extruded material in the usual manner employed in the productionthereof whereby said alcohol is automatically substantially eliminated.

3. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding into an aqueous bath a cellulosic solution containing pine oil, and finishing the extruded material in the usual manner employed in the production thereof whereby said pine oil is automatically substantially eliminated.

4. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding into an aqueous bath a cellulosic solution containing a substance compris ing alpha-terpineol, and finishing the extruded material in the usual manner employed in the production thereof whereby said terpineol is automatically substantially eliminated.

. 5. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding into an aqueous bath a cellulosic solution containing 0.05% to 3.0% by weight of an alcohol containing more than 4 carbon atoms and a vapor pressure such that it will not be removed from the solution prior to extrusion and will be automatically removed in the usual finishing operations employed in the production of the product, and finishing the ex-- truded material in the usual manner employed in the production thereof whereby said alcohol is automatically substantially eliminated.

6. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding into an aqueous bath a cellulosic solution containing 0.05% to 3.0% by weight of a substance comprising an alcohol of the terpene group, and finishing the extruded material in the usual manner employed in the production thereof whereby said alcohol is automatically substantially eliminated.

7. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding into an aqueous bath a cel.

lulosic solution containing 0.05% to 3.0% by weight of pine oil, and finishing the extruded material in the usual manner employed in the production thereof whereby said pine oil is automatically substantially eliminated.

8. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding into an aqueous bath a cell'ulosic solution containing 0.05% to 3.0% by weight of a substance comprising alpha-terpineol, and finishing the extruded material in the usual manner employed in the production thereof whereby said terpineol is automatically substantially eliminated.

9. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding a viscose solution containing an organic substance of more than 4 carbon atoms and containing one or more hydroxyl groups, said substance possessing a vapor pressure such that it will not be removed from the solution prior to extrusion and will be automatically removed in the spinning and in the subsequent operations employed in the production of the product, and finishing the extruded material in the usual manner employed in the production thereof whereby said organic substance is automatically substantially eliminated.

10. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding a viscose solution containing a substance comprising an alcohol of the terpene group, and finishing the extruded material in the usual manner employed in the produc tion thereof whereby said alcohol is automatically substantially eliminated.

11. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding a viscose solution containing pine oil in a viscose solution, and finishing the extruded material in the usual manner employed in the production thereof whereby said pine oil is automatically substantially eliminated.

12. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding a viscose solution containing a substance comprising alpha-terpineol, and finishing the extruded material in the usual manner employed in the production thereof whereby said terpineol is automatically substantially eliminated.

13. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding a viscose solution containing 0.05% to 3.0% by weight of an alcohol containing more than 4 carbon atoms and a vapor pressure such that it will not be removed from the solution prior to extrusion and will be automatically removed in the usual finishing operations employed in the production of the product and finishing the extruded material in the usual manner employed in the production thereof whereby said alcohol is automatically substantially eliminated.

14. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding a viscose solution containing 0.05% to 3.0% by weight of a substance comprising an alcohol of the terpene group, and finishing the extruded material in the usual manner employed in the production thereof whereby said alcohol is automatically substantially eliminated.

15. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding a viscose solution containing 0.05% to 3.0% by weight of pine oil, and finishing the extruded material in the usual manner employed in the production thereof whereby said pine oil is automatically substantially eliminated.

16. A method for producing sheets, films, threads and the like characterized by a low luster which comprises extruding a viscose solution 'containing 0.05% to 3.0% by weight of a substance comprising alpha-terpineol, and finishing the extruded material in the usual manner employed in the production thereof whereby said terpineol is automatically substantially eliminated.

1'7. A method for producing sheets, films, threads and the like characterized by a low luster which comprises incorporating in a viscose solution at some stage in the manufacture thereof an emulsion containing an alcohol having more than 4 carbon atoms and a vapor pressure such that it will not be removed from the solution prior to extrusion and will be automatically removed in the spinning and in the subsequent operations employed in the production of the product in such quantities that from 0.05 to 3.0% of said alcohol is added, extruding said solution, and finishing the extruded material in the usual manner employed in the production thereof whereby said alcohol is automatically substantially eliminated.

18. A method for producing sheets, films, threads and the like characterized by a low luster which comprises incorporating in a viscose solution at some stage in the manufacture thereof an emulsion containing a substance comprising an alcohol of the terpene group in such quantities that from 0.05% to 3.0% of said alcohol is added, extruding said solution, and finishing the extruded material in the usual manner employed in the production thereof whereby said alcohol is automatically substantially eliminated.

19. A method for producing sheets, films, threads and the like characterized by a low luster which comprises incorporating in a viscose solution at some stage in the manufacture thereof an emulsion containing pine oil in such' quantities that from 0.05% to 3.0% of said pine oil is added, extruding said solution, and finishing the extruded material in the usual manner employed in the production thereof whereby said pine oil is automatically substantially eliminated.

20. A method for producing sheets, films, threads and the like characterized by a low luster which comprises incorporating in a viscose solution at some stage in the manufacture thereof an emulsion containing a substance comprising alpha-terpineol in such quantities that from 0.05% to 3.0% of said terpineol is added, extruding said solution, and finishing the extruded material in the usual manner employed in the production thereof whereby said terpineol is automatically substantially eliminated.

21. A method for producing sheets, films, threads and the like characterized by a low luster which comprises incorporating 0.4% by weight of alpha-terpineol in a viscose solution at some stage in the manufacture thereof, extruding said solution, and finishing the extruded material in the usual manner employed in the production thereof whereby said terpineol is automatically substantially eliminated.

EMIL KLINE.

o a 6 CERTIFICATE OF CORRECTION.

Patent No. 2,042,944. June 2, 1956.

EMIL KLINE.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, first column, line 45, after the word "than" insert that; and line 54, before "special" insert any; page 2, first column, lines 26 to 57 inclusive, strike out the table and insert instead the following:

Amylene dichloride 0.4% emulsified with Monopole oil Tetrachlorethane 0.5% Tetrachlorethylene 0.4% Fenchyl alcohol 0.4% Terpinedl 0.4% Nekal A. E. M. Pine oil' 0.6% triethanolamine oleate and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 18th day of August, A. D. 1936.

Hen'r Van (Seal) Acting commissioner of paifii 

